Nonlinear Dyn (2017) 88:1691–1705
DOI 10.1007/s11071-017-3339-y
ORIGINAL PAPER
Solving Painlevé paradox: (P–R) sliding robot case
Hesham A. Elkaranshawy · Khaled T. Mohamed ·
Ahmed S. Ashour · Hassan M. Alkomy
Received: 9 July 2016 / Accepted: 6 January 2017 / Published online: 26 January 2017
© Springer Science+Business Media Dordrecht 2017
Abstract For a rigid body or a multibody system
sliding on a rough surface, a range of uncertainty or
non-uniqueness of solution could be found, which is
termed: Painlevé paradox. Painlevé paradox is the rea-
son of a wide range of undesired bouncing motions
which are observed during sliding. As Painlevé para-
dox is a practical problem in case of multibody systems,
this research work has investigated that paradox. In this
research work, the condition leading to Painlevé para-
dox has been determined for a general multibody sys-
tem. Investigating the motion of a prismatic–revolute
(P–R), sliding robot has been conducted. In order to
solve the paradox and find the motion, a tangential
impact is assumed at the contact point. The impact
model has been developed and the paradox, conse-
quently, has been solved. Consequently, the kinematics
of the motion has been specified.
Keywords Painlevé paradox · Tangential impact ·
Friction · Multibody systems · Robot dynamics
H. A. Elkaranshawy · A. S. Ashour · H. M. Alkomy (B )
Department of Engineering Mathematics and Physics,
Faculty of Engineering, Alexandria University, Alexandria,
Egypt
e-mail: eng.alkomy@gmail.com;
h.m.alkomy@alexu.edu.eg
K. T. Mohamed
Department of Mechanical Engineering, Faculty of Engineering,
Alexandria University, Alexandria, Egypt
1 Introduction
The motion of multibody systems may face many
dynamical problems and obstacles which affect their
functional operation. These problems may occur due
to several reasons; geometrical reasons, force-related
reasons, material reasons… etc. These dynamical prob-
lems could influence the motion dramatically. Self-
locking for some parallel robots is one of these dynam-
ical problems that may lead to either a sudden stop
during the robot’s motion or even inability to start the
motion [1]. One of these problems, which has deep
effect on the motion of sliding robots, is the undesired
bouncing motion. Good understanding of this prob-
lem and modeling it, using the classical mechanics
concepts, are so important for the dynamical analy-
sis and control issues. Pushing a chalk on a blackboard
is one of the simplest and best examples of the unde-
sired bouncing motions. Sometimes during the push-
ing process, the chalk leaves the blackboard and shows
detachments [2]. The cause of bouncing motion may
be some external forces and inertia actions or may be
due to the configuration and contact parameters such
as lengths, masses and/or the coefficient of friction.
Liu et al. [3] discussed the difference between these
two main sources of bouncing motion and found many
valuable results. In this research, we devote ourselves
to study the bouncing motion in robotic systems related
to the configuration and contact parameters, as one of
the common problems that needs intensive research.
Exactly, we study the bouncing motion that occurs for
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